Method for controlling items belonging to a commissioning order and a device for carrying out said method

ABSTRACT

Disclosed are a method and an arrangement for checking items ( 3 ) belonging to a commissioning order and transported on a conveyor path ( 1 ) with respect to product type and number of items ( 3 ) by aid of sensing devices ( 10 ) connected with a computer ( 4 ′). Here, each one of the items ( 3 ) is optically or opto-electronically, respectively, checked, optionally after having been individualized and aligned, while being transported.

[0001] The invention relates to a method for checking items belonging toa commissioning order and transported on a conveyor path with respect toproduct type and number of items by aid of sensing devices connectedwith a computer.

[0002] Moreover, the invention relates to an arrangement for carryingout the method.

[0003] At present, in large warehouses, items are aranged manually,semiautomatically or automatically to groups of goods according tocommissioning orders and collected in containers. For checking purposes,the containers are guided to weighing devices in the dispatching regionso as to compare the net weight of the container contents with the sumof the individual weights of the items. Since in many instances,particularly in the pharmaceutical whole sale business, productsweighing less than 10 g are in circulation, checks may often yieldincorrect results. A check for the type of product by such a weighingprocedure is hardly possible and also difficult, respectively, sincemany different products have approximately the same weight. Thus, thereis a demand for a control which enables a safe check for the type ofproduct and the number of products.

[0004] From DE 691 10 852 D2 a method is known for the commissioning ofitems which are removed from the compartments of shelves bycommissioners by hand, are identified by means of a bar code readingdevice, weighed, and subsequently dropped into an empty or alreadypartially filled container. The containers are transported on a mainconveyor path so as to be shifted onto one or several secondary conveyorpaths which consist of non-driven rollers; adjacent each secondaryconveyor path, a manually displaceable checking device is arranged inwhich identification and weighing of the items are effected by thecommissioner. The containers arriving at the checking device are alsoidentified by means of a bar code reading device, and all the datasensed are monitored by a central computer so as to monitorcorrespondence of the items commissioned in the containers with thecommissioning order; at each checking device, a screen with a keyboardis additionally provided for interactive communication of thecommissioner with the central computer. This method thus provides for acheck of the items during the commissioning procedure itself, the modeof procedure being comparatively complex and still uncertain.

[0005] In EP 572 830 B1 a method of identifying, labelling and targetingof goods at the input of goods and/or at the output of goods in awarehouse is described. By “goods”, cartons of equal or different sizescontaining items are to be understood. These cartons pass a checkingstation in which a plausibility check takes place, namely whether or notthe previously effected identification, weight and volume are inagreement. For identification purposes, a reading device is providedwhich preferably also consists of six scanners to scan the cartons onall sides or to read the information printed on a label; the read actualdata are transmitted to a computer for a comparison with the set data.In this method, however, checking of the items themselves which arecontained in the cartons does not take place so that there, too, thedisadvantages explained above prevail.

[0006] It is thus the object of the invention to provide a method of theinitially defined kind as well as an arrangement for carrying out themethod by which a precise, in particular automatic, checking of theindividual items is carried out while they are being commissioned so asto safely locate faulty groups of goods which do not exactly correspondto a commissioning order.

[0007] According to the invention, this object is achieved in thepresent method in that each item as such is optically oropto-electronically checked while being transported. Due to the factthat the individual items are each separately optically oropto-electronically detected and recognized, this method allows for asafe checking of the items, and advantageously it can be employed notonly in new commissioning installations but also in already existingones so as to completely exclude faulty deliveries, which is ofparticular importance in case of pharmaceutical products.

[0008] With a view to a rapid, automatic and safe checking, it isadvantageous if the items are individualized prior to their beingchecked. Thereby the items can be scanned or “read”, respectively, oneafter the other.

[0009] In this connection it is also advantageous if the items arealigned prior to checking; they may thus be brought into a certainlongitudinal or transverse orientation which, although preferred—neednot necessarily be done since there exist multidirectional electronicscanners, e.g., which can also detect the bar code of non-longitudinallyaligned items.

[0010] If the items have already been commissioned into containers,according to the invention it is of particular advantage for thechecking if the items which have been assembled in a container accordingto a commissioning order are removed from the container before each ofthem is checked. Prior to such a check, the items may be individualizedand aligned, respectively, as mentioned above. Such a mode of procedureallows groups of items to be put together in the usual manner accordingto the respective commissioning orders and still to be safely checkedautomatically as desired for any mistakes which may have occurred duringcommissioning.

[0011] With comparatively poorly identifyable imprints on the items ithas also proven advantageous if the items are temporarily stopped whilebeing checked.

[0012] Furthermore, it is suitable if the items, in case of a negativeresult of the check, subsequently are corrected respectively in terms oftype and number of products. Subsequently, the item groups initiallyfound to be incorrect can be delivered immediately so as to comply withthe commissioning order without having to start commissioning anew.

[0013] Moreover, it is advantageous if the items of a negative checkresult can be removed automatically thus obviating a time-consuminglater, in particular manual, search for the faulty items.

[0014] For the rational course of commissioning also during checking ithas furthermore proven advantageous if the items are transferred into acontainer after having been checked. In this manner, the items whichhave yielded a positive checking result can be passed on immediately asa complete group of goods, e.g. for packing and delivery thereof. Toreduce the number of containers which are in circulation, it is alsosuitable if, after checking, the items are transferred into thatcontainer which originally contained them.

[0015] To effectively shorten the checking procedure, it is particularlyadvantageous if several items are checked simultaneously.

[0016] In an arrangement for carrying out the method, it is providedthat the conveyor path comprises a checking station with automaticallyoperating optical or opto-electronical, respectively, sensing devicesassociated therewith or arranged to follow the former. By thisarrangement, minimal time is required as compared with checking carriedout by hand, whereby not only the working time as such with the costsassociated therewith can be saved, but also commissioning orders can becompleted even more rapidly—and with certainty.

[0017] Advantageously it can also be provided that a container-emptyingstation is associated with the conveyor path and that therebehind analigning and individualizing station is arranged which is followed bythe checking station. By this arrangement, the items can be suitablyprepared for the checking procedure proper by being individualized andlongitudinally aligned so that misreadings by the sensing devices areexcluded. Checking of the individual items themselves on the other handgives a practically 100% certainty of the check for the correctness ofthe assembled groups of goods.

[0018] A preferred, advantageous embodiment consists in that thechecking station comprises a chute formed at least partially oftransparent material, at which the optical or opto-electronical sensingdevices are arranged transversely to its longitudinal direction. On thechute which is downwardly inclined by e.g. 30°, the items move past thesensing devices without requiring a separate drive, e.g. a vibrationdrive, or a separately driven conveyor path therefor whose structuremight constitute an optical impediment to the recognition procedure.

[0019] A particularly advantageous embodiment provides for the chute tohave a V-shaped cross-section. In this case it is suitable if the legsof the chute enclose an angle of 90° with each other. In this manner,the items come to lie snugly with two of their longitudinal side faceson the two legs of the V-shaped chute, resulting in ideal conditions foran optical identification.

[0020] Advantageously it can also be provided for the checking stationto be formed by a path of small rollers. Between adjacent rollers, alsothe lower side of the items can be checked, while the upper side and thelongitudinal side of the items are freely accessible to begin with. Ifthe path of small rollers is arranged to be inclined, this variant doesnot require an additional drive either.

[0021] In terms of complete automation, it is furthermore particularlyadvantageous if the checking station is followed by a device forautomatically removing the items.

[0022] In tests, it has proven particularly suitable if as the sensingdevices, at least two, preferably four, scanners or video cameras arearranged opposite each other. In this manner, imprints or codes on theitems or even their entire appearance can be compared with storedcomparative information so as to determine the correctness of the itemsin a simple and absolutely certain manner. It has proven suitable iffour scanners or video cameras are arranged opposite each other inpairs.

[0023] If due to poorly identifyable imprints on the items misreadingscould occur while they are being moved, it is suitable if a stoppingdevice for the items is arranged in the region of the sensing devices.In this case it is particularly advantageous if the stopping devicecomprises a solenoid. To stop the items, the solenoid need only beoperated for a short time resulting in practically no delay of thepassage of the items.

[0024] According to a preferred embodiment of the invention it isprovided for the aligning and individualizing station to be formed byseveral, e.g. laterally offset conveyor paths conveying the items atdifferent speeds. This arrangement in practice has yielded very goodresults, individualizing and aligning of the items being effected in arelatively short period of time. For an alignment of the items whilethey are being individualized, it is also advantageous if the firstconveyor path(s) is (are) provided with directing plates for directingthe items to the (respective) consecutive conveyor path. With a view toindividualizing, it is suitable if the conveying speeds increase fromone respective conveyor path to the next conveyor path.

[0025] The invention will be further explained by way of preferredexemplary embodiments to which, however, it shall not be restricted, andwith reference to the drawings.

[0026]FIGS. 1 and 2 each show a schematic top view onto an arrangementfor carrying out the method according to the invention;

[0027]FIG. 3 shows a part of the arrangement according to FIG. 1 infront view, partially in cross-section, according to line III-III ofFIG. 1 or FIG. 2, respectively;

[0028]FIG. 4 shows a part of a further arrangement in side view; and

[0029]FIG. 5 shows a schematic top view onto an example of a device forautomatically removing items arranged to follow the checking station.

[0030] In FIG. 1, a conveyor path is denoted by 1, which moves items 3dispensed individually and consecutively by an automat 2 according to acommissioning order to a checking station 4 in which the items 3 arechecked in terms of product type and number. Before the items 3 reachthe checking station 4, they are directed to the middle of the conveyorpath 1 by directing plates 5, 6 so as to fall on a chute 7 which isinclined downwardly in transportation direction by 30°, the chute havinga V-shaped cross-section, as is visible in FIG. 3. The directing plates5, 6 may be omitted if the chute 7 and the conveyor path 1 have equalwidths.

[0031] The chute 7 is at least partially comprised of a transparentmaterial, preferably glas or transparent plastics, and its legs 8, 9enclose an angle of 90° so that two longitudinal side faces of thecuboid items 3 can lie snugly thereon. Approximately in the longitudinalmiddle of the chute 7, sensing devices 10, e.g. four scanners, inparticular bar code scanners, e.g. multidirectional bar code scanners,which can also sense transversely arranged bar codes, are arrangedtransversely to the longituidnal direction of the chute, or four videocameras 11 a to 11 b (cf. also FIG. 3), whose optical axes are orientedperpendicularly to the legs 8, 9 or to the four longitudinal side facesof the items 3, respectively. In this manner, either a bar code, a mark,an insript, a figure on the longitudinal side faces and/or the contourof the items 3 can be detected optically and transformed into electricsignals which are transmitted to a computer 4′. In this connection itmay be provided that always only one of the items 3 is sensed—fromcertain sides or from all sides—, however, if the video cameras 11 orthe scanning devices (e.g. several scanning devices adjacently arrangedon one level) are suitable therefor, also simultaneous seinsing ofseveral items can be carried out; what is essential is that each one ofthe items 3 is sensed. By aid of a bar code or sign or picturerecognition program stored in the computer 4′, which optionally is alsosuitable for simultaneously recognizing several items, both the producttype and the number of items 3 can be checked thereby and compared witha commissioning order. The result may be displayed for the operatingpersonnel on a screen 12 arranged in the region of the chute 7.

[0032] From the chute 7, the items 3 drop into a container 13 wich istransported on a conveyor path 14 and stopped at the chute 7.

[0033] If the computer 4-determined result of the check regarding thetype of product and number of items 3 is in agreement with thecommissioning order, the container 13 is passed on via the conveyor path14 to a delivery or packing station (not illustrated). If there is noagreement, the container 13′ is transferred outwardly to an area ofdeposit 15, and the operating personnel can correct the contents of thecontainer 13′ on the basis of the data displayed on the screen 12 andoptionally transmit the correction effected to the computer via akeyboard (not illustrated).

[0034] In the exemplary embodiment illustrated in FIG. 2, the containers16 filled with items 3 according to a commissioning order reach acontainer-emptying station 18 via a conveyor path 17, e.g. a rollerconveyor path or a conveyor belt, at which the containers 16 are stoppedand are tilted either manually or, preferably, automatically, e.g. via atilting ledge or by aid of gripping means etc. (not illustrated indetail), generally by means of a tilting device 19, to empty theircontents, i.e. the items 3, onto a conveyor path of an aligning andindividualizing station 20. The tilting device 19 illustrated indot-and-dash lines lifts the respective container 16, e.g. at the rearbottom edge, and tilts it over the front bottom edge; the tilting device19 may also lift the container 16 at its collar, transport it to theconsecutive aligning and individualizing station 20 and tilt it there.

[0035] In the example illustrated, the aligning and individualizingstation 20 consists of three laterally offset conveyor paths 21, 22 and23, their conveying speeds V1, V2, V3 increasing from the foremostconveyor path 21 onto which the items 3 are emptied from the containers16 up to the last conveyor path 23, the items 3 at the end of theforemost and middle conveyor paths 21, 22 each being detoured bydirecting plates 24, 25 to the consecutive conveyor path 22, 23.Preferably, the second conveying speed V2 is twice as high as the firstconveying speed V1, and is the third conveying speed V3 in turn twice ashigh as the second conveying speed V2. By this, a rapid longitudinalalignment of the items in the manner of an “entrainment” andindividualization of the items 3 can be achieved.

[0036] It is, of course, also possible to carry out individualization ofthe items 3 on conveyor paths which are consecutively aligned in oneline and each have a higher conveying speed, wherein optionally alsofunnel-like arranged directing plates may help in the individualizingprocedure.

[0037] Alignment and individualizing of the items 3 in the aligning andindividualizing station 20 could furthermore be effected manually,particularly on a relatively slowly moving conveyor path (notillustrated); it may also be completely omitted, if respective sensingdevices 10 are provided which are able to sense several items in randompositions on the basis of their contours as well as imprints; in thisinstance, the sensing devices 10 must have the entire width of theconveyor path in their “field of vision”.

[0038] According to FIG. 2, the aligning and individualizing station 20again is followed by the checking station 4 including the sensingdevices 10 whose construction and mode of function have already beendescribed before by way of FIGS. 1 and 3, thus obviating any furtherdescription.

[0039] From the chute 7 of the checking station 4, the items 3 againdrop into the container 16 which in the meantime has been manually or,preferably, automatically taken from the emptying station 18 and putonto the conveyor path 26, and moved to the chute 7, e.g. by means ofthe tilting device 19 correspondingly designed for transversedisplacement, or by a separate transverse displacement device, e.g. witha pneumatically actuated slide (not illustrated), and has been stoppedat the chute 7. (A tilting device 19 which could be employed here is,e.g., the one according to DE 30 45 145 A1).

[0040] If the computer 4′-determined result of the check regarding thetype of product and number of items 3 is in agreement with thecommissioning order, the container 16 with the items 3 is then passed onvia a conveyor path 26′ to a delivery or packing station, respectively(not illustrated). If there is no agreement, the container 16′ is againtransferred outwardly to an area of deposit 15, and the operatingpersonnel may again correct the contents of the container 16′ on thebasis of the data indicated on the screen 12 and optionally transmit thecorrection effected to the computer 4′ via a keyboard (not illustrated).

[0041]FIG. 4 illustrates a variant of a checking station 4 comprising amodified “chute” 7′ in the form of an inclined path 27 of small rollers.The sensing devices 10 comprise two oppositely arranged (bar code)scanners or video cameras 11′b, 11′c with optical axes extending betweentwo of the small rollers 27 a of the path 27 of small rollers. Moreover,two scanners or video cameras 11′a, 11′d having horizontal optical axesmay be provided, as has been indicated in FIG. 4 in broken lines. Itshould be mentioned here that also in the exemplary embodiment accordingto FIG. 3, only two (or three) bar code scanners or video cameras couldbe employed instead of four bar code scanners or video cameras 11 a-11d.

[0042] Laterally of the path 27 of small rollers and for guiding theitems 3 longitudinally, according to FIG. 4 directing plates 28 arearranged, preferably of transparent material. To allow for an exactreading or optical recognition in the resting state of the items 3, herealso a stopping device 29 is provided which is, e.g., formed by asolenoid 30 having a plunger core 31 which extends to between twoneighboring small rollers 27 a following the sensing devices 10. Thesolenoid 30 is excited for a short time, e.g., by the signal of aphotoelectric barrier (not illustrated), so that the passage of theitems 3 is only slightly delayed.

[0043] Instead of chutes 7, 7′, also two conveyor belts (notillustrated) may be arranged consecutively, a sufficiently wide gapbeing left clear at the site of transition between the two conveyorbelts so as to allow for an optical scanning of the items through thisgap.

[0044] In the two exemplary embodiments according to FIGS. 1 and 2, alsoa device 32 illustrated in FIG. 5 for outwardly transferring thoseindividual items 3 which have given rise to a negative checking resultmay be arranged downstream of the checking station 4 or of the chute 7,7′, respectively. This device 32 is, e.g., a chute 33 following upon thechute 7, 7′, and provided with a pivot arm 34 to be actuatedelectrically via the computer or pneumatically, which pivot armlaterally detours the items 3 found to be incorrect, towards the edge ofthe chute 33 so that they then will drop into a container 35 providedthere. Instead of the pivot arm 34, also a drop flap (not illustrated)may be provided.

[0045] Items 3 which have given rise to a positive checking result, onthe other hand reach their conveyor path either directly via chute 33,or they get into a container 13 or 16, respectively, on the conveyorpath 14 or 26′, respectively, so as to be directed towards the deliveryor packing station, respectively.

1. An arrangement for checking items (3) belonging to a commissioningorder and transported on a conveyor path (1) with respect to producttype and number of items (3) by aid of automatically operating opticalor opto-electronical, respectively, sensing devices (10) which areconnected with a computer (4′), to which sensing devices (10) the items(3) are supplied on a conveyor path (1), characterized in that thesensing devices (10) are arranged in a transverse plane to a conveyor inthe form of an at least partially transparent chute (7), a path (27) ofsmall rollers or of two conveyor belts with a clear gap therebetween,which conveyor allows for a visibility therethrough.
 2. An arrangementaccording to claim 1, characterized in that a container-emptying station(18) is associated to the conveyor path (1) and that therebehind analigning and individualizing station (20) is arranged which is followedby the sensing devices (10).
 3. An arrangement according to claim 1 or2, characterized in that the chute (7) has a V-shaped cross-section. 4.An arrangement according to claim 3, characterized in that the legs (8,9) of the chute (7) enclose an angle of 90° with each other.
 5. Anarrangement according to any one of claims 1 to 4, characterized in thatthe sensing devices (10) are followed by a device (32) for automaticallytransferring the items (3) outwardly.
 6. An arrangement according to anyone of claims 1 to 5, characterized in that as the sensing devices (10),at least two scanners or video cameras (11 a, 11 d) are arrangedopposite each other.
 7. An arrangement according to claim 6,characterized in that four scanners or video cameras (11 a to 11 d) arearranged opposite each other in pairs.
 8. An arrangement according toany one of claims 1 to 7, characterized in that a stopping device (29)for the items (3) is arranged in the region of the sensing devices (10).9. An arrangement according to claim 8, characterized in that thestopping device (29) comprises a solenoid (30).
 10. An arrangementaccording to any one of claims 2 to 9, charcaterized in that thealigning and individualizing station (20) is formed by several, e.g.laterally offset, conveyor paths (21, 22, 23) conveying at differentspeeds.
 11. An arrangement according to claim 10, characterized in thatthe first conveyor path(s) (21, 22) is (are) provided with directingplates (24, 25) for directing the items (3) to the (respective)consecutive conveyor path (22, 23).
 12. An arrangement according toclaim 10 or 11, characterized in that the conveying speeds (V1, V2, V3)increase from conveyor path (21, 22) to conveyor path (22, 23).